DE1023037B - Process for the preparation of 6- or 7-acetyl-1, 1, 3, 4, 4-pentamethyl- or -7-acetyl-1, 1, 3, 4, 4, 6-hexamethyl-1, 2, 3, 4-tetrahydronaphthalene - Google Patents

Description

Process for the preparation of 6- or 7-acetyl-1,1,3,4,4-pentamethyl or. -7-Acetyl-1,1,3,4,4,6-hexamethyl-1, 2,3,4-tetrahydronaphthalene Most known Musky compounds fall into two classes of compounds: 1. nitrated aromatic compounds such as musk xylene, which is 2,4,6-trinitro-1,3, -dimethyl-5-tert.-butylbenzene, and 2. macrocyclic ketones, lactones or esters, such as cyclopentadecanone, cyclopentadecanolide and ethylene brassylate.

Although the links in the first group are cheap to manufacture, they suffer from the disadvantage that they are not lightfast and alkali-resistant, whereby them in products, e.g. B. soap, often cause discoloration. Limbs of the second Group, although they are sufficiently resistant to light and alkali, difficult to manufacture and relatively expensive.

For the production of musk fragrances it was known from p-cymene and starting from tertiary amyl chloride, whereby the third alkyl group is a tertiary Amyl group is introduced into the benzene ring. Then it is then with acetyl chloride acetylated. In this process, hydrocarbons are obtained as by-products, which in the subsequent acetylation lead to compounds that cause an unpleasant Introduce odor component into the musky-smelling acetyl derivative. Through this the fragrance quality of the end product is impaired.

It was also known to use musk fragrances based on nitrobutylcumene and to produce indane compounds that are also not of the desired purity and have stability.

It has now been found that 6- or 7-acetyl-1,1,3,4,4-pentamethyl-1 , 2,3,4-tetrahydronaphthalene and 7-acetyl-1,1, 3,4,4,6-hexamethyl-1, 2,3,4-tetrahydronaphthalene have the desirable property of having a musky fragrance character to have, but extremely stable to light and alkali and also inexpensive to manufacture are.

The new musk compounds are made by taking benzene or toluene with 2,2,5,5-tetramethyltetrahydro-3-furanol in the presence of anhydrous Aluminum chloride reacts as a condensing agent, the compound obtained in the presence dehydrated by sulfuric acid, the dehydrated compound in the usual way reacts with methyl magnesium iodide according to Grignard, the compound obtained in the presence dehydrated by p-toluenesulfonic acid, the compound obtained in the presence of Sulfuric acid and cyclized the cyclized compound in a known manner with acetyl chloride acetylated in the presence of aluminum chloride.

The process according to the present invention is thus directed to the preparation of tetrahydronaphthalene derivatives and enables the synthesis of tetrahydronaphthalenes of the following structure: R means hydrogen or methyl.

It is easy to see that the new musk-like compounds can be used in a wide variety of preparations. The products can e.g. B. be used in perfumes, cosmetics in general and soaps.

The following examples illustrate the practice of the invention.

Example 1 6- or 7-acetyl-l, l, 3,4,4-pentamethyl-1, 2,3,4-tetrahydronaphthalene a) 2,2,5,5-Tetramethyltetrahydro-3-furanol: This compound was catalytic Hydrogenation of the known 2,2,5,5-tetramethyltetrahydro-3-furanone in an autoclave made of stainless steel, whereby 282 g of ketone in the presence of 20 g of copper chromite catalyst at about 35 to 42 at and 140 to 144 "with Hydrogen hydrogenated. The yield of 2,2,5,5-tetramethyltetrahydro-3-furanol, a colorless one, at room temperature solidifying liquid, bp 3 = 63 63 to 64 ° D. = 0.9498, n25 = 1.44t9, F. = 27 °, freezing point 26.5 ", purity 99 0j0, was quantitative. B) 2,5-dimethyl-5-phenyl-2,3-hexanediol : Into a stirred suspension of 148 g of granular, anhydrous aluminum chloride and 500 g of benzene became a solution of 72 g of the above at room temperature 2,2,5,5-Tetramethyltetrahydro-3-furanols in 100 g of benzene, whereby the Maintained temperature at 20 to 25 °. After two hours of stirring at 35 to 40 ° was the solution was quenched on 1000 g of pieces of ice with thorough stirring. The benzene solution was separated from the water and successively with water, 5% sodium carbonate solution and washed water again. After distilling off the benzene, the product became distilled in vacuo. The 2,5-dimethyl-5-pheny1-2,3-hexanediol was used in an amount of 65 g (58.5 01o of theory) obtained as viscous oil, bp 2 = 126 to 128 °, nD ° = 1.5190. c) 2,5-Dimethyl-5-phenyl-3-hexanone: In 400 g of stirred 300/0 sulfuric acid 111 g of 2,5-dimethyl-5-phenylexane-2,3-diol were in the course at the reflux temperature introduced by 1 hour. The mixture was then stirred for an additional hour heated to reflux and finally distilled with steam until the distillate was almost oil-free. The distillate consisted of 77 g of oil and 5.635 g of water. The oil was distilled in vacuo, and there were 66 g of 2,5-dimethyl-5-phenyl-3-hexanone, Kp. A = 97 to 101.5 °, nD20 = 1.5048 to 1.5070. d) 2,3,5-trimethyl-5-phenyl-3-hexanol : To a Grignard solution, made from 15 g of magnesium shavings, 205 g of absolute Ether and 88 g of methyl iodide were at reflux temperature (34 °) 126 g of the above 2,5-dimethyl-5-phenyl-3-hexanones, dissolved in 126 g of dry ether, are added. That The reaction mixture was refluxed for 1 hour after the addition. After this Quenching on 125 g of ice, 125 g of water and 33 g of ammonium chloride and work-up 99.0 g of 2,3,5-trimethyl-5-phenyl-3-hexanol were obtained in the usual way, Kp 4.5 = 119 to 123 °, nD20 = 1.5103. The product was a viscous colorless liquid and odorless. e) 2,3,5-Trimethyl-5-phenyl-2-hexene: In a suitably equipped The device was a solution of 250 g benzene, 99 g 2,3 2,3,5-trimethyl-5-phenyl-3-hexanol and 0.25 g of p-toluenesulfonic acid and stirred with separation of water under reflux heated. After removing almost the theoretical amount of water, the solution became neutralized, filtered, and the benzene was distilled off. With vacuum distillation of the remaining liquid was 73.5 g of 2,3,5-trimethyl-5-phenyl-2-hexene obtained, Kp.2 = 82 to 92 °, nD ° = 1.5023 to 1.5131. f) 1,1,3,4,4-pentamethyl - 1,2,3,4 - Tetrahydronaphthalene: In 75 ccm kept at 0 ° and stirred 930/0 Sulfuric acid gave 71 g of 2,3,5-trimethyl-5-phenyl-2-hexene in the course of 3/4 hour brought in. After the addition, the mixture was stirred at 0 ° for a further 3/4 hour and quenched on 150g pieces of ice. There were 100 cc of benzene for relief added to the separation of the benzene. After washing with water, then 5% sodium hydroxide solution and again with water, the benzene was distilled off and the product in vacuo distilled. 59 g of 1,1, S, $, PPentamethyl-l. , 2,3,4-tetrahydronaphthalene obtained as a colorless, almost odorless liquid. Kp.2,5 = 103 to 104 °, n20o = 1.5204. g) 6- or 7-acetyl-1,1,3,4,4-phentamethyl-1,2,3,4-tetrahydronaphthalene: In a mixture of 38.5 g of anhydrous Aluminum chloride in 135 g of ethylene dichloride became a dropwise over the course of one hour (20 to 25 °) at room temperature Solution of 50.5 g of the 1,1,3,4,4-pentamethyl-1,2,3,4-tetrahdyronophthalene described above and 22.5 g of acetyl chloride are added. The temperature was then increased to 40 ° and that Stirring continued for 30 minutes. After quenching on ice, the mixture was broken down and washed the oil neutral. After distilling off the ethylene dichloride was the remaining oil is distilled in vacuo over 0.5 g of sodium carbonate. There were 35 g of the desired 7-acetyl-1,1,3,4,4-pentamethyl-1, 2,3,4-tetrahydronaphthalene, Kp2. = 125 to 127 °, nD20 = 1.5349 as a colorless viscous liquid with a lasting, obtained musky odor. The acetyl group can be in either the 6- or 7-position are located.

Analysis for C17 H24O: Calculated ...... C 83.60%, H 9.83%; found ......... C 83.48 0 / o, H 9.740 / o.

Example 2 Preparation of 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene a) 2,5-Dimethyl-5-p-tolyl-2,3-hexanediol: In a stirred suspension of 148 g granular, anhydrous aluminum chloride and 500 g of toluene is at room temperature a solution of 72 g of the above-described 2,2,5,5-tetramethyltetrahydro-3-furanol added to 100 g of toluene, keeping the temperature at 20 to 25 °.

After two hours of stirring at 35 to 40 °, the solution was under good Stirring quenched on 1000 g pieces of ice. The toluene solution was separated from the water and successively with water, 5% sodium carbonate solution and again with water washed. After removal of the toluene and vacuum distillation of the product were 74 g of 2,5-dimethyl-5-p-tolyl-2,3-hexanediox were obtained, boiling point l = 127 to 128 °, nD20 = 1.5192.

Analysis for C15H24O2: Calculated ........ C 76.3%, H 10.17%; found ....... C 76.25%, H 10.00%. b) 2,5-Dimethyl-5-p-tolyl-3-hexanone: Stirred in 400 g 300/0 sulfuric acid became 118 in the course of one hour at the reflux temperature Introduced g of 2,5-dimethyl-5-p-tolyl-2,3-hexanediol. The mixture then became a stirred and refluxed for a further hour. Then a steam distillation followed, until the distillate was almost oil-free. The distillate consisted of 78.5 grams of oil and 5.710 g of water. The oil was distilled in vacuo, and 48 g of 2,5-dimethyl-5-p-tolyl-3-hexanone, Kp. L = 96 to 105 °, 1X20 = 1.5088 to 1.5095. c) 2,3,5-trimethyl-5-p-tolyl-3-hexanol: In one made from 9 g of magnesium shavings, 122 g of anhydrous ether and methyl iodide Grignard solution was a solution of 73 g of 2,5-dimethyl-5-p-tolyl-3-hexanone at reflux temperature (34 °) given in 73 g of ether. The solution was refluxed 1 hour after the addition heated and then quenched on 100 g of ice chips and 100 g of water. The mixture was carefully acidified by slowly adding 137 g of 100/0 hydrochloric acid with stirring. The ether solution was worked up in the usual way and 66 g of 2,3,5-trimethyl-5-p-tolyl-3-hexanol obtained by distillation, colorless viscous liquid, b.p. 2 = 105 to 109 °, nD20 = 1.5108.

The yield was 84.7% of theory. d) 2,3,5-trimethyl-5-p-tolyl-2-hexene: In a suitably equipped apparatus, a solution of 200 g of benzene, 66 g 2,3,5-trimethyl-5-p-tolyl-3-hexanol and 0.25 g of p-toluenesulfonic acid and stirred under separation refluxed by water. After separation of almost the theoretical amount of water, the solution was neutralized with sodium carbonate, filtered and the benzene was distilled off. In the vacuum distillation of the remaining 51.0 g of 2,3,5-trimethyl-5-p-tolyl-2-hexene were obtained in liquid, boiling point 1 = 88 up to 95 °, n200 = 1.5085 to 1.5157.

The yield was 83.6% of theory. e) 1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronophthalene: 93% sulfuric acid, which was kept at 0O in 55 cc and stirred, slowly increased 48 g of 2,3,5-trimethyl-5-p-tolyl-2-hexene were introduced three quarters of an hour. To the addition, the mixture was stirred for a further three quarters of an hour at 0 °, and Quenched to 120 g of ice chips. 100 cc of benzene were added to reduce the To facilitate separation of the oil. The solution was after using them one by one Water, 5% sodium hydroxide solution and washed again with water to remove the Benzene distilled. The remaining oil was distilled in vacuo, whereby 35.5 g of colorless 1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene were obtained, bp 2 = 90 to 93 °, n2D0 = 1.5216.

The yield was 75% of theory. f) 7-Acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene: In a mixture of 24.0 g of anhydrous aluminum chloride in 100.0 g of ethylene dichloride was added dropwise, at room temperature (20-25 °) over the course of one hour a solution of 35.0 g of 1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahdyronaphthalene in 14.0 g of acetyl chloride were added. Then the mixture was further 30 minutes at 40 ° touched. After quenching on 200 g of ice, the mixture was broken down and the ethylene dichloride solution was washed neutral. After removal of the ethylene dichloride was the remaining Oil washed in vacuo with 0.5 g of sodium carbonate solution. It became what I wanted 7-Acetyl-11 3 446 -hexamethyl-1,2,3,4-tetradhydronaphthalene, a colorless viscous liquid with a strong and persistent musky odor. The yield was 24.5 g, bp 2.5 = 144 °, nD20 = 1.5359.

Analysis for C18H26O: Calculated .......... C 83.75%, H 10.07%; found C 83.74%, H 9.89 C / o.

For the production of 2,2,5,5-tetramethyltetrahydro-3-furanol protection is not claimed within the scope of the present invention.

Claims (1)

PATENT CLAIM: Process for the production of 6- or 7-acetyl-1,1,3,4,4-pentamethyl- or 7-acetyl-1 1 3 44 6-hexamethyl-1, 2,3,4-tetrahydronaphthalene, characterized in that that benzene or toluene in the presence of anhydrous aluminum chloride with 2,2,5,5-tetramethyltetrahydro-3-furanol reacts, the 2, 5-dimethyl-5-phenyl- or -5-p-tolyl-2,3-hexanediol formed with Sulfuric acid dehydrated, the resulting 2,5-dimethyl-5-phenyl- or -5-p-tolyl-3-hexanone reacted in the usual way with methyl magnesium iodide according to Grignard, the obtained 2,3,5-trimethyl-5-phenyl- or -5-p-tolyl-3-hexanol in the presence of p-toluenesulfonic acid dehydrated, the 2,3,5-trimethyl-5-phenyl- or -5-p-tolyl-2-hexene formed cyclized with sulfuric acid and the 1,1,3,4,4-pentamethyl- or 1,1,3,4,4,6-hexamethyl-1 , 2,3,4-tetrahydronaphthalene in the usual way with acetyl chloride in the presence of Acetylated aluminum chloride. Documents considered: German Patent No. 918 747; Dutch Patent No. 74524; Helv. Chim. Acta, Vol. 15, 1932, pp. 592 to 596; Journ. am. Chem. Soc., Vol. 70, 1948, pp. 2123-2128.